In the present study we examined the processing demands of three reading comprehension tests, namely the Woodcock-Johnson Passage Comprehension (WJPC), a Curriculum-Based Measure test (CBM-Maze), and a Recall test, in the early elementary years. Our investigation was theoretically motivated by Perfetti's Verbal Efficiency Theory and examined the contribution of a set of skills that are important in early reading (i.e., rapid naming, phonological processing, orthographic processing, fluency, vocabulary, and working memory) to the three reading comprehension tests. Furthermore, because this set of skills undergo rapid development in the early years, we assessed them in two consecutive years, Grade 1 and Grade 2, before examining their prediction to the three reading comprehension tests in Grade 2. The findings showed that the three reading comprehension tests pose different demands to the young reader. Implications of these findings are discussed with respect to reading comprehension assessment and diagnosis of reading difficulties. (Contains 2 tables and 3 figures.)